Fix #8

Assume `hostnameDict = Object.create(null)`

Ideally this should always be the case.

src/js/dynamic-net-filtering.js

@@ -168,9 +168,6 @@ Matrix.prototype.copyRules = function(other, srcHostname, desHostnames) {
 
     // Specific destinations
     for ( var desHostname in desHostnames ) {
-        if ( desHostnames.hasOwnProperty(desHostname) === false ) {
-            continue;
-        }
         ruleKey = '* ' + desHostname;
         ruleValue = otherRules[ruleKey] || 0;
         if ( ruleValue !== 0 ) {

src/js/messaging.js

@@ -336,7 +336,7 @@ var popupDataFromTabId = function(tabId, tabTitle) {
         r.noRemoteFonts = µb.hnSwitches.evaluateZ('no-remote-fonts', rootHostname);
         r.remoteFontCount = pageStore.remoteFontCount;
     } else {
-        r.hostnameDict = {};
+        r.hostnameDict = Object.create(null);
         r.firewallRules = getFirewallRules();
     }
     r.matrixIsDirty = !µb.sessionFirewall.hasSameRules(

src/js/popup.js

@@ -124,9 +124,6 @@ var cachePopupData = function(data) {
     }
     var domain, prefix;
     for ( var hostname in hostnameDict ) {
-        if ( Object.prototype.hasOwnProperty.call(hostnameDict, hostname) === false ) {
-            continue;
-        }
         domain = hostnameDict[hostname].domain;
         prefix = hostname.slice(0, 0 - domain.length);
         // Prefix with space char for 1st-party hostnames: this ensure these
@@ -254,7 +251,7 @@ var updateFirewallCell = function(scope, des, type, rule) {
 
     // Remember this may be a cell from a reused row, we need to clear text
     // content if we can't compute request counts.
-    if ( Object.prototype.hasOwnProperty.call(popupData.hostnameDict, des) === false ) {
+    if ( popupData.hostnameDict[des] === undefined ) {
         cells.removeAttr('data-acount');
         cells.removeAttr('data-acount');
         return;